Like everyone else has said, you have to do it for you. I quit May, 1998. It wasn't easy. I used Nicorette gum. This might not work for you, be willing to try anything. If you have ever met anyone with emphezma, that should really make you stop.
There is not just the physical addiction side to stopping. There is also a psychological side as well. Not smoking anymore is like loosing a friend. Cig's are something you have probably had with you for a long time. You had to make time to smoke, you looked forward to smoking and it was good. Breaking old habits of when you would smoke is hard. For example: with that first cup of coffee in the morning, driving, after sex. Each time you get to one of these important times, you have to make a consciece effort to not smoke. Remember, if you have that one cigerete, you will no longer be a non-smoker! Good luck, there are many ex-smokers in this world. Use them to help YOU become a former smoker as well.